Piano

ABSTRACT

An improved upright piano having a case with a reverberating sound chamber secured about the exterior of the case and the vertical sounding board of the piano. Said reverberating sound chamber establishes a harp-shaped wall of which the lateral edges are secured to the back side of the case. A secondary sounding board is engaged to the back side of the case adjacent to and spaced from said sounding board.

[ PllANO [76] Inventor:

- States Patent [22] Filed:

Edmund S. Goss, 3561 Homestead Road, Santa Clara, Calif. 95051 FOREIGN PATENTS OR APPLICATIONS Nov. 15, 1971 11/1939 France ..84/240 531,107 12/1940 Great Britain... 491,985 9/1938 Great Britain ..84/177 21 19 512 Primary Examiner-Richard B. Wilkinson Assistant Examiner-John F. Gonzales Att0rneyThomas E. Schatzel [52] US. Cl ..84/189, 84/192 [51] int. 131. ..G10c 3/06 [57] ABSTRACT [58] Field of Search ..84/177, 186, 189, 192, 194,

84/240 An improved upright piano having a case with a reverberating sound chamber secured about the exterior of the case and the vertical sounding board of the piano. [56] References cued Said reverberating sound chamber establishes a harp- UNITED STATES PATENTS shaped wall of which the lateral edges are secured to the back side of the case. A secondary sounding board 2,530,251 11/1950 Luberofi ..84/ 177 X is engaged to the back side of the case adjacent to and 1,679,290 7/ 1928 spaced from said sounding board. 2,412,212 12/1946 Gerlat 2,532,286 12/1950 Brown ..84/177 X 5 Claims, 3 Drawing Figures ill . PAT

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PIANO This invention relates in general to a new and improved piano and more particularly to a new and improved upright piano.

A conventional piano generates tones by means of an action of levers which control felt hammers in turn adapted to move and strike one or more taunt steel strings. The hammers are under the control of the player or performer. The strings vibrate responsive to the strikes of the hammer. The velocity and force of the hammers are controlled by the performer such that the amplitude and tonal characteristics of the resultant sound are dependent on the skill of the performer. Conventional pianos are designed such that when the strings vibrate, they transmit pressure differences to a bridge attached to an elastic sound board. The bridge is adapted to support the strings across the inner face of the sound board and to provide a connection between the sound source and the sound board. The sound board is, in turn, set in motion thereby agitating the air in its immediate vicinity to radiate the sound. The manner in which the sound board radiates the sound is a factor of the volume and quality of the tones produced by the piano.

In upright type pianos, including spinet type pianos, the sound board is supported in a vertical plane and is positioned towards the back of the piano case with the strings supported across the inner face in a vertical array parallel to the sound board. Upright pianos have generally been designed to conserve space and to make said instruments compatible for use in homes or other areas having space limitations.

In grand pianos the sound board and supported sound strings are positioned in a horizontal plane. Such pianos have been generally recognized as having greater volume and tonal qualities over that of upright designed pianos. Grand pianos also are generally viewed to have more favorable design attributes. At the same time, the economic cost to build such pianos are significantly greater than that of the upright and spinet designs.

SUMMARY OF THE PRESENT INVENTION The present invention relates to an improved piano of the type having a vertical sound board. The present invention provides a piano case, especially upright type pianos, in which a reverberating chamber is supported about the back of the piano case to improve the tonal qualities and sound projections. The reverberating chamber about the back side of the case may include a harp-shaped vertical wall with an interior horizontal tone reflection board to establish a chamber opening towards the bottom of the case. A secondary sounding board is mounted vertically about the back of the case in spaced intermediate adjacent relationship to the primary sounding board and vertical wall of the reverberating chambers. The secondary sounding board is adapted to channel tone waves towards the horizontal tone reflection board.

In operation, the piano of the present invention provides an upright vertical piano with an acoustic chamber about the backside adapted to catch the partial tones and channel them to a tone chamber which may be of similar structural shape to that of a grand piano. The reverberant or reflective tones in an exemplary embodiment are channeled upward and blended and then directed downward providing a vibrant tonal quality and imitating the tonal complexities similar to that of a horizontal grand piano.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an upright piano incorporating the teachings of the present invention;

FIG. 2 is a perspective view of the reverberatingsecondary sounding board assembly of the piano of FIG. 1; and

FIG. 3 is a front view of the piano of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT The drawings illustrate a piano incorporating the teachings of the present invention and referred to by the general reference character 1. The piano 1 may comprise a conventional upright piano having a case 3 with a wooden vertical sounding board 5 supporting a plurality of vertical strings 7 joined to a bridge 9 about the front face of the board 5. The sounding board 5 closes off the back of the case 3. The backside of the board 5 is joined to a plurality of vertical stiffening braces 10 and diagonal ribs 11. The braces 10 and ribs 11 provide the board with sufficient rigidity to support the strings while allowing it to have sufficient flexibility to radiate sound energy from the strings to the air. A plurality of felt hammers 12 are linked to keys of a keyboard 13. In operation, as the performer strikes select keys on the keyboard 13, associated hammers l2 strike associated strings 7 such that the primary sounding board 5 vibrates and radiates sound about the piano. A substantial portion of the sound is radiated about the back side of the piano case 3.

The piano 1 further includes a reverberating sound chamber referred to by the general reference character 15. The reverberating chamber 15 has a vertical wooden harp-shaped wall 17 similar to the familiar shape of a grand piano. The lateral edges of the wall 17 are secured about the back side of the case 3 at a position adjacent to the top. The lateral edges of the wall 17 are secured to the side walls of the case 3. As positioned, the reverberating chamber 15 is positioned in adjacent spaced relationship to the primary sounding board 5. The wall 17 assumes a harp-shaped curvature, like in a grand piano, such that the lateral spacing of the wall 17 from the primary sounding board varies. The spacing increases adjacent to the long strings relative to that of the short strings. The vertical wall 17 has a top horizontal edge 18 and a lower horizontal edge 19. The wall 17 extends vertically with the top edge 18 coinciding with the top edge of the case and primary sounding board 5 and the bottom edge 19 to a second horizontal plane intermediate the top terminal edge of the case 1 and lower terminal edge of the sounding board 5. A wooden horizontal reflection board 20 is positioned normal to the vertical wall 17 with the peripheral edge of the board 20 engaged to the interior wall surface of the vertical wall 17. The board 20 is engaged to the wall 17 at a location immediate the top and bottom horizontal edges of the wall 17 so as to establish a pair of tonal chambers 21 and 23. Tonal chamber 21 opens towards the top of the case 3 and the tonal chamber 23 opens towards the bottom of the case 3.

An acoustical chamber is formed by a curved secondary sounding board 25 positioned about the back side of the case 3 in spaced, adjacent relationship parallel to the primary sounding board 5 and the vertical wall 17. The board 25 is curved to have a varying degree of lateral spacing from the primary sounding board 5 as it extends horizontally across the back side of the board 5. The degree of curvature is substantially less than that of the wall 17 such that the board is intermediate the sounding board 5 and wall 17 and there is lateral spacing between the wall 17 and board 25 intermediate the vertical edges of the wall 17 and board 25. The secondary sounding board 25 has vertical terminal edges 26 and 27 secured to the vertical edge of the case and primary sounding board 5 by means of a plurality of screws or dowels 28.

The secondary sounding board 25 forms an opening about the bottom edge of the case 3 intermediate the primary sounding board 5. The secondary sounding board 25 extends vertically from a horizontal position coinciding approximately with the lower edge of the primary sounding board 5 to a horizontal position within the tonal chamber 23. The secondary sounding board 25 establishes an opening about its top edge opening to the tonal chamber 23. The spacing adjacent to the longest strings 7 on the primary sounding board 5 is greater than that about the shorter strings 7 similar to that of the wall 17 of the reverberating chamber 15. The secondary sounding board 25 may be of a material similar to that of the primary sounding board. The secondary sounding board 25 tends to be set into vibration by the acoustic waves set up by the primary sounding board 5. Since the secondary sounding board 25 is not rigidly bound along the horizontal edges, it is free to vibrate at all frequencies developed in the piano. The secondary sounding board 25 is believed to channel tonal waves upwards to the tonal chamber 23. The first reflected tone waves are channeled up and using the chamber principle of secondary tonal reflections are then directed to and rebound from the horizontal board 20 downward to the exterior through the opening intermediate the board 25 and the edge 19 of the wall 17. Sound also penetrates toward the horizontal member 20 to the exterior of the case 3 and chamber 21. The opening about the lower terminal edge of the secondary sounding board 25 permits it to channel sounds to the exterior of said case 3.

The piano 1 is further characterized by a plurality of sound chambers 29 opening about the front side of the casing 3 to facilitate channeling of sound to the front of the piano 1. The piano 1 further carries a pivotable cover 30 of a shape similar to that ofa grand piano.

It has been found that a piano constructed according to the teachings of the present invention relative to a conventional upright piano having the usual exposed primary sounding board about the back side, is characterized in increased volume of sound projected towards the front of the piano, less harsh tones and a sound of more pleasing tonal quality. The tone is modified by the reverberating chamber and secondary sounding board 25 so as to produce a more mellow tone. At the same time, the piano 1 may assume the shape of a grand piano and make a significant aesthetic contribution with either the front, back or side exposed.

lclaim:

1. In an upright piano having a case with strings vertically supported about a vertical primary sound board mounted on the case adjacent to the strings such that said primary sound board is capable of resonating tones produced by the strings, the improvement comprising:

a reverberating sound chamber secured to the back side of the case about the exterior of said primary sound board, the reverberating sound chamber establishing a vertical harp-shaped wall laterally spaced from and adjacent to said primary sound board, the reverberating sound chamber being engaged about its lateral edges to the case adjacent the lateral vertical edge of said primary sound board, the top edge of said harp shaped wall terminating at substantially the same height as the case and the bottom edge of the harp-shaped wall terminating intermediate of the top and bottom edge of said primary sound board, a horizontal reflection member extending normal to said vertical wall, the peripheral edge of the horizontal sound chamber being engaged to the interior wall surface of the vertical wall at a position intermediate the top and bottom edges of said vertical wall to form a first and a second tonal chamber within said reverberating chamber, said first tonal chamber opening to the exterior atmosphere about the top edge of said vertical harp-shaped wall and the second tonal chamber opening to the exterior atmosphere about the bottom edge of said vertical harp-shaped wall; and

a secondary sounding board secured to the back side of the case about the exterior of said primary sound board, the secondary sounding board extending vertically about said case adjacent to and laterally spaced from said primary sound board and the secondary sounding board and opening to within said second tonal chamber to channel sound to within said second tonal chamber, the top edge of the secondary sounding board terminating intermediate the top and bottom edge of said primary sound board and the bottom edge of the secondary sound board terminating adjacent to the bottom edge of the primary sound board.

2. The piano of claim 1 in which the secondary sounding board is engaged about its vertical peripheral edges to said case adjacent to the lateral vertical edges of said primary sounding board, said secondary sounding board being curved intermediate the vertical terminal ends to provide a varying lateral spacing between the vertical sound board and said secondary sounding board intermediate the vertical peripheral edges.

3. The piano of claim 2 in which the vertical wall of the reverberating chamber extends vertically from a first plane coinciding with the top edge of the case to a second plane intermediate the lower terminal edge of the case and said first plane;

the secondary sounding board extends vertically from approximately said second plane to a third plane coinciding approximately with the lower terminal edge of the primary sound board; and

the lateral spacing of the vertical wall of the reverberating chamber relative to said primary sound board intermediate the vertical edges of the vertiterior atmosphere of said case. 5. The piano of claim 4 further including at least one sound chamber opening about the front side of said case to channel sound to the exterior atmosphere about the front side of said case. 

1. In an upright piano having a case with strings vertically supported about a vertical primary sound board mounted on the case adjacent to the strings such that said primary sound board is capable of resonating tones produced by the strings, the improvement comprising: a reverberating sound chamber secured to the back side of the case about the exterior of said primary sound board, the reverberating sound chamber establishing a vertical harp-shaped wall laterally spaced from and adjacent to said primary sound board, the reverberating sound chamber being engaged about its lateral edges to the case adjacent the lateral vertical edge of said primary sound board, the top edge of said harp shaped wall terminating at substantially the same height as the case and the bottom edge of the harp-shaped wall terminating intermediate of the top and bottom edge of said primary sound board, a horizontal reflection member extending normal to said vertical wall, the peripheral edge of the horizontal sound chamber being engaged to the interior wall surface of the vertical wall at a position intermediate the top and bottom edges of said vertical wall to Form a first and a second tonal chamber within said reverberating chamber, said first tonal chamber opening to the exterior atmosphere about the top edge of said vertical harp-shaped wall and the second tonal chamber opening to the exterior atmosphere about the bottom edge of said vertical harp-shaped wall; and a secondary sounding board secured to the back side of the case about the exterior of said primary sound board, the secondary sounding board extending vertically about said case adjacent to and laterally spaced from said primary sound board and the secondary sounding board and opening to within said second tonal chamber to channel sound to within said second tonal chamber, the top edge of the secondary sounding board terminating intermediate the top and bottom edge of said primary sound board and the bottom edge of the secondary sound board terminating adjacent to the bottom edge of the primary sound board.
 2. The piano of claim 1 in which the secondary sounding board is engaged about its vertical peripheral edges to said case adjacent to the lateral vertical edges of said primary sounding board, said secondary sounding board being curved intermediate the vertical terminal ends to provide a varying lateral spacing between the vertical sound board and said secondary sounding board intermediate the vertical peripheral edges.
 3. The piano of claim 2 in which the vertical wall of the reverberating chamber extends vertically from a first plane coinciding with the top edge of the case to a second plane intermediate the lower terminal edge of the case and said first plane; the secondary sounding board extends vertically from approximately said second plane to a third plane coinciding approximately with the lower terminal edge of the primary sound board; and the lateral spacing of the vertical wall of the reverberating chamber relative to said primary sound board intermediate the vertical edges of the vertical wall is greater than the lateral spacing of the secondary sounding board relative to said vertical primary sound board intermediate the vertical edges of the secondary sounding board.
 4. The piano of claim 3 in which the secondary sounding board establishes an opening about said third plane to channel sounds to the exterior atmosphere of said case.
 5. The piano of claim 4 further including at least one sound chamber opening about the front side of said case to channel sound to the exterior atmosphere about the front side of said case. 